How to change a pending comment to an approved one

Greetings, I posted a comment and it says your comment is awaiting moderation. Why is it saying this? I have posted the comment twice and it says the same thing. I've gone into my dashboard to change the status from pending to approved but even though I hit apply, it doesn't apply. Can anyone tell me how to change the status of this pending comment to approve and how to delete the duplicate that I've made?